The present invention relates generally to a stitching tool useful for tying tissues with sutures, typically in endoscopic surgery.
Stitching tools for tying tissues with sutures in endoscopic surgery are well known. U.S. Pat. Nos. 5,364,408; 5,458,609; 5,540,704; 5,575,800 and 5,578,044, all assigned to Laurus Medical Corp., Irvine, Calif., USA, are drawn to a family of suturing systems and needle drivers marketed under the name Push and Catch(trademark). The needle driver automatically captures and retrieves sutures for tying sutures in tissues.
A disposable suturing device marketed under the trademark Endo Stitch(copyright) by United States Surgical Corp., Norwalk, Conn., USA, is another known device for tying sutures in tissues in endoscopic surgery.
The present invention seeks to provide a stitching tool useful for suturing and ligation of tissues in endoscopic procedures, such as Burch urethropexy, oophorectomy, cholecystectomy, myomectomy, hysterectomy, trocal wound closure and paravaginal repair.
There is thus provided in accordance with a preferred embodiment of the present invention a stitching tool including a needle including an arcuate shank having an arcuate length extending from a needle point at one end thereof to another end, called a suture end, and wherein the needle is toothed along at least a portion of the length.
In accordance with a preferred embodiment of the present invention the suture end is adapted for attachment thereto of a suture.
Further in accordance with a preferred embodiment of the present invention the arcuate shank defines a curve having at least one focus and the needle is toothed along a surface furthest from the at least one focus.
Additionally in accordance with a preferred embodiment of the present invention the stitching tool includes a needle manipulator including a housing with an arcuate channel formed therein through which moves the needle, the channel defining an arc extending from a first end to a second end, wherein as the needle moves through the channel, the needle point exits the housing at the first end and re-enters the housing at the second end and the arc is sufficiently long such that at least one of the needle point and the suture end is always in the channel during moving of the needle. The stitching tool also preferably includes an actuator for moving the needle through the channel. Preferably the actuator is coupled to the needle by a toothed belt which meshes with the toothed needle.
Preferably the arcuate channel defines a curve having at least one focus and the needle is rotatable about the focus at least 360xc2x0.
Instead of the needle being toothed, a standard, smooth arcuate needle may be employed as well. The actuator may move the needle by means of a belt snugly fit between the needle and the arcuate channel. The surface of the belt which contacts the needle has a higher coefficient of friction than the surface of the belt which contacts the channel. The belt presses against the needle and as the actuator moves the belt, the belt moves the needle by means of friction through the channel.
There is also provided in accordance with a preferred embodiment of the present invention a stitching tool including a needle including an arcuate shank having an arcuate length extending from a needle point at one end thereof to another end, called a suture end, and a needle manipulator including a housing with an arcuate channel formed therein through which moves the needle, the channel defining an arc extending from a first end to a second end, wherein as the needle moves through the channel, the needle point exits the housing at the first end and re-enters the housing at the second end and the arc is sufficiently long such that at least one of the needle point and the suture end is always in the channel during moving of the needle.
Additionally in accordance with a preferred embodiment of the present invention the arcuate channel is bounded by a disc, which rotates about the at least one shank focus, and an upper housing portion. The disc has an axle disposed in an enlarged hole so that the axle can translate within the boundary of the enlarged hole, and the disc can rotate eccentrically about the at least one shank focus.
In accordance with a preferred embodiment of the present invention the disc includes a rim with a surface that is contactable with the needle and the upper housing portion includes a surface that is contactable with the needle, wherein the rim contacting surface has a higher frictional contact with the needle than the upper housing portion contacting surface.
The disc may be pulled (because of the axle being in the enlarged hole) so that the rim of the disc presses the needle against the upper housing portion. Once the needle is pinched between the disc and the upper housing portion, rotation of the disc causes rotation of the needle due to the difference in coefficient of friction between the needle/rim contact and the needle/housing contact.
Further in accordance with a preferred embodiment of the present invention the stitching tool includes a link eccentrically attached to the disc, wherein pulling of the link in a direction away from a centerline of the disc causes the disc to impart an advancing angular movement to the needle. Pulling the link first pinches the needle between the disc and the upper housing portion and further pulling of the link, due to its eccentric mounting to the disc, causes the disc and the needle to rotate about the at least one shank focus.
Still further in accordance with a preferred embodiment of the present invention the disc includes a first half and a second half, and a link is attached to the first half, wherein pulling of the link in a direction away from a centerline of the disc causes the first half of the disc to impart an advancing angular movement to the needle and pushing the link in a direction towards the centerline causes the second half of the disc to press against the needle and to prevent regressive angular movement of the needle opposite to the advancing angular movement.